Angiopoietin-1 protects neurons by inhibiting autophagy after neuronal oxygen-glucose deprivation/recovery injury.

Angiopoietin-1 (Ang-1) is a new neuroprotective agent, which can protect neurons from apoptosis. Increased autophagy in neurons subjected to oxygen-glucose deprivation/recovery (OGD/R) injury may lead to autophagic cell death; therefore, the present study investigated the effect of Ang-1 on neurons subjected to OGD/R injury. Neuronal viability was detected by using the Cell Counting Kit-8, which was then used to select the appropriate concentration of Ang-1 and rapamycin used in the OGD/R injury model. The mechanistic role of Ang-1 was observed by detecting the survival rate of neurons and the level of autophagy. Results showed that Ang-1 significantly reduced neuronal cell injury induced by OGD/R and the expression of the autophagy-related proteins LC3 II/I and Beclin-1, and increased the expression of P62/SQSTM1. However, the neuroprotective effects of Ang-1 were counteracted by rapamycin, an autophagy activating agent. The changes of autophagy intensity were further confirmed by transmission electron microscopy observation of autophagosomes. Ang-1 appears to have a neuroprotective role by inhibiting autophagy expression in OGD/R. Thus, these findings could be useful for the treatment of OGD/R injury.